1. Field of the Invention
The present application relates to cervical traction devices that are used to distract cervical vertebra for relieving pain and discomfort associated with cervical misalignment and compression.
2. Description of Related Art
Vertebral traction machines and vertebral decompression machines (collectively referred to herein as “vertebral distraction machines”) have been successfully used to treat vertebral misalignment and compression in people suffering mild to severe back pain. By applying a distractive force to the vertebra, the machines are able to assist in decompressing or realigning the affected vertebra, thereby relieving the associated pain. Although some machines have been developed for home use, most vertebral distraction machines are operated by a skilled therapist or doctor.
Typically, the vertebral distraction machine includes a system for applying the distractive force to a patient lying on a platform or bed of the machine. In most cases, distraction of the vertebra in the back is accomplished by attaching a harness to the waist or legs of the patient. The harness is typically connected to either a flexible rope, cable, or webbing, and a force is applied to pull on the lower body of the patient while the upper body remains stationary. The application of force may be accomplished by hanging weights from the rope, cable, or webbing, but it is more common to apply force using a winch that is turned by a clutch-operated motor. The winch is housed in a pedestal at the foot of the bed on which the patient lies, and the therapist directs the application of force by controlling the clutch-operated motor.
Since it is difficult to isolate the cervical vertebra using lower body harnesses, cervical traction devices have been provided as “add-on” components for vertebral distraction machines. These add-on components typically include a movable head support that is positioned beneath the head of a patient lying on the bed of the distraction machine. The person's head is secured to the movable head support and a force is applied to the head support using ropes, cables, or webbing attached through pulleys to the winch at the pedestal. The primary problem with this method of cervical distraction is that it provides an indirect, flexible power transfer linkage between the motor applying force and the patient's head. This flexible linkage prevents efficient control of the force. Additionally, the forces required for cervical traction are much less than those required for lower vertebral traction; therefore, the conventional motor associated with vertebral distraction machines is oversized and mismatched for applying cervical distraction forces. Some cervical traction devices employ motors positioned nearer to the head of the patient, but these motors are also connected to the patient's head using flexible power transfer equipment such as ropes, cables, and webbing. These devices suffer the same control problems described above.
An additional problem associated with existing cervical traction devices is the unsafe condition that can be created during a power interruption. The clutch-operated motors used with most cervical traction devices completely disengage when power to the motor is interrupted. For a patient undergoing cervical treatment, the rapid relaxation of the cervical distraction force could be painful and cause injury. It would be much preferred to be able to slowly relax the cervical distraction force in the event of a power loss.
A need therefore exists for an improved cervical traction device that eliminates the flexible power transfer equipment associated with existing cervical traction devices. A need further exists for a cervical traction device that does not require use of an outsized and remotely located motor that is used for lower vertebral distraction. Finally, a need exists for a cervical traction device that allows gradual reduction in the cervical distraction force in the event of a power loss or interruption.